Experience has taught us Cannes veterans to cast a wary eye down the right-hand column of the press screenings schedule, where the running times of the competition films are listed.

Producers and directors quite often submit self-indulgently long versions of their movies to test the patience of the critics. The result is that many movies are returned to the editing room afterwards and pruned before being deemed suitable for public consumption.

Nine of the 20 films in competition this year run for longer than two hours, and several others fall just minutes short of that. Richard Kelly, who at 31 is the youngest director in competition, follows his cultish Donnie Darko with the longest movie in competition, Southland Tales, which clocks in at two hours and 40 minutes and faces the acid test of a press screening timed for 8.30 next Sunday morning. The eclectic cast includes The Rock and Sarah Michelle Gellar (pictured), as well as Seann William Scott and Miranda Richardson.

Finnish director Aki Kaurismaki has the distinction of producing the shortest competition entry, The Lights in the Suburbs, which is exactly half the length of Kelly's magnum opus. Does size matter? We'll see.